Telephony devices, such as telephones, analog fax machines, and data modems, have traditionally utilized circuit-switched networks to communicate. With the current state of technology, it is desirable for telephony devices to communicate over the Internet, or other packet-based networks. Heretofore, an integrated system for interfacing various telephony devices over packet-based networks has been difficult due to the different modulation schemes of the telephony devices. Accordingly, it would be advantageous to have an efficient and robust integrated system for the exchange of voice, fax data and modem data between telephony devices and packet-based networks.
Such devices usually include some form of automatic gain control to compensate for losses when a signal progresses through the system. Telephony devices might typically include at least one echo canceling device to compensate for the echo return loss (ERL) that might occur in transmitting a signal from a near end to a far end, and vice versa. This echo canceling device can be used to provide a wealth of information regarding the processed signal. Accordingly, what is needed in the field is a gain control device that uses certain information provided by the echo canceling device in order to provide a more stable automatic gain control.